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The maximum number of nonredeemable preferred shares (or preferred stock redeemable solely at the option of the issuer) permitted to be issued by an entity's charter and bylaws.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.5-02.28)

-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 29

-Article 5

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- Definition

Aggregate share number for all nonredeemable preferred stock (or preferred stock redeemable solely at the option of the issuer) held by stockholders. Does not include preferred shares that have been repurchased.

+ References

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- Definition

Number of shares that have been repurchased and retired during the period.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 04

-Article 3

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 505

-SubTopic 10

-Section 50

-Paragraph 2

-URI http://asc.fasb.org/extlink&oid=6928386&loc=d3e21463-112644

Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 29, 30

-Article 5

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- Definition

Equity impact of the value of stock that has been repurchased and retired during the period. The excess of the purchase price over par value can be charged against retained earnings (once the excess is fully allocated to additional paid in capital).

+ References

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- Definition

Number of shares that have been repurchased during the period and have not been retired and are not held in treasury. Some state laws may govern the circumstances under which an entity may acquire its own stock and prescribe the accounting treatment therefore. This element is used when state law does not recognize treasury stock.

+ References

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- Definition

Equity impact of the value of stock that has been repurchased during the period and has not been retired and is not held in treasury. Some state laws may mandate the circumstances under which an entity may acquire its own stock and prescribe the accounting treatment therefore. This element is used when state law does not recognize treasury stock.

+ References

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- Definition

Amount of stock repurchase plan authorized.

+ References

No definition available.

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- Definition

Period which shares may be purchased under a stock repurchase plan authorized by an entity's Board of Directors, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

No definition available.

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- Definition

Amount remaining of a stock repurchase plan authorized.

+ References

No definition available.

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- Definition

Total cost of shares repurchased divided by the total number of shares repurchased.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 505

-SubTopic 30

-Section 45

-Paragraph 1

-URI http://asc.fasb.org/extlink&oid=6405813&loc=d3e23239-112655

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Stockholders' Equity Narrative (Details) (USD $) Share data in Millions, except Per Share data, unless otherwise specified	12 Months Ended
	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011	Jan. 31, 2011
Class of Stock [Line Items]
Stock Repurchased During Period, Value	$ 5,608,000,000	$ 688,000,000	$ 705,000,000
Stock Repurchased and Retired During Period, Value	5,300,000,000
Stock Repurchased and Retired During Period, Shares	59
Treasury Stock Acquired, Average Cost Per Share	$ 90.29
Preferred Stock, Shares Authorized	5us-gaap_PreferredStockSharesAuthorized	5us-gaap_PreferredStockSharesAuthorized
Preferred Stock, Shares Outstanding	0us-gaap_PreferredStockSharesOutstanding	0us-gaap_PreferredStockSharesOutstanding
Common Stock [Member]
Class of Stock [Line Items]
Stock Repurchased During Period, Shares	62	12	21
2014 Stock Repurchase Program [Member]
Class of Stock [Line Items]
Stock Repurchase Program, Authorized Amount	5,000,000,000
Stock Repurchased During Period, Value	2,000,000,000
Stock Repurchase Program, Remaining Authorized Repurchase Amount	3,000,000,000
Stock Repurchased and Retired During Period, Shares	19
Treasury Stock Acquired, Average Cost Per Share	$ 103.87
2011 Stock Repurchase Program [Member]
Class of Stock [Line Items]
Stock Repurchase Program, Period in Force				3 years 0 months 0 days
Stock Repurchase Program, Authorized Amount					5,000,000,000
Stock Repurchased During Period, Value	$ 3,300,000,000	$ 582,000,000	$ 667,000,000
Stock Repurchased and Retired During Period, Shares	40	10	23
Treasury Stock Acquired, Average Cost Per Share	$ 83.75	$ 60.78	$ 28.93